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The control cable (drive cable) is a flexible, steel cable with an outer helical winding. The length of control cable is
approximately twice the length of the remote controls. Attached to one end of the control cable is a male connector. The
control cable, when used in conjunction with the remote control as a system, provides a positive mechanical control of
the source assembly at a distance. The control cable is a critical link for safe operation and is the radiographer's only
means of control over the source assembly. Therefore, the control cable's storage, use, daily inspection and quarterly
maintenance are critical elements to the prevention of a control cable failure.
In almost all cases, repairs for a control cable are not possible, with the exception of replacing the control cable's Model
550 male connector every five years. Damaged, defective or control cables with an unknown origin (non-traceable) must
not be used and must be removed from service.
1) Uncoil the remote controls at the site. Inspect the control crank to assure all fastening screws are present and
tightened and that the crank handle is properly secured. If the control crank is equipped with an odometer, zero the
odometer while the control cable is fully retracted. Verify the odometer is fully functional.
2) Ensure the instructions on the control crank's label are legible. These written instructions are important to safety,
especially when assistants are being trained or during an emergency. Without the written instructions it is
conceivable a radiographer could become confused as to which direction the crank handle must be turned to
“retract” or “expose” the source.
3) Ensure the brake is operational. Resistance should be felt while rotating the crank handle with the brake in the
“ON” position. Inspect the control conduit fittings to verify they are secured to the control crank.
4) Drive Cable Inspections
i. Inspect the control cable connector as it protrudes out of the connecting plug assembly. The control cable
connector should not be bent or at an angle exceeding 15 degrees relative to the control cable centerline. If a
control cable connector is repeatedly bent at an angle greater than 15 degrees, damage to the control cable
may be introduced by straightening the bend. Inspect the control cable (male) connector to verify that the
stem and ball of the connector are not bent or cracked.
Using hand pressure, attempt to twist the control cable connector from the control cable. If the control cable
connector can be twisted using hand pressure or appears bent or cracked, remove from service and label as
defective.
ii. Pull approximately 12 in (30.5 cm) of control cable out of the connecting plug assembly and inspect for the
following anomalies directly behind the connector:
• Cuts, breaks, nicks or fraying of the spiral windings of the control cable.
• Areas with kinks or permanent bends.
• Rust (a red oxide) on the inner core of the control cable.
• Uniformity of the spacing between the outer spiral windings. Also check for flattened areas and wear.
• Bend the connector section of control cable back towards itself and release the cable to test for flexibility
or ‘spring’ of the control cable. A cable that has been subjected to the flexibility test and remains in the
bent position after the test provides an indication of internal corrosion and must be removed from
service.
• Verify that a light coating of mil-spec grease, approved by QSA Global, Inc., is present on the control
cable. The light coating of grease is necessary to prevent the penetration of water and chemicals that can
oxidize and permanently damage the control cable.
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